Index_B

B

B channel, 234, 526

B8ZS (Binary 8-Zero Substitution), 525

back end, 526

backbone, 526

backbone area, for OSPF, 361

backbone routers

in IS-IS, 380

in OSPF, 362

backup designated router (BDR), 526

in OSPF, 357, 359, 362–363

backward explicit congestion notification (BECN), 243, 419, 526

balanced hybrid routing, 324–325

bandwidth, 526

and congestion, 69

consumption, 91

for link-state router, 323

as OSPF metric, 368

for routing updates in distance-vector protocols, 315

as WAN design criteria, 223

bandwidth command, 341

baseband, 526

Basic Rate Interface (BRI), 234, 527

baud, 526

Bc (Committed Burst), 243, 526

BDR (backup designated router), 526

in OSPF, 357

beacon, 526

BECN (backward explicit congestion notification), 243, 419, 526

BGP version 4 (BGP4), 526

binary, 527

Binary 8-Zero Substitution (B8ZS), 525–526

binding, 13, 527

BIP (bit interleaved parity), 527

BISDN (broadband ISDN), 527

bit-oriented protocol, 527

blocked port, for Spanning-TreeProtocol, 85

border gateway, 527

bottleneck, 23–24

information gathering about, 163

Bpdu (Bridge Protocol Data Unit), 84, 527

BRI (Basic Rate Interface), 234, 527

uses, 235

bridge-group virtual interface (BVI), 390

bridge ID, for Spanning-Tree Protocol, 84

Bridge Protocol Data Unit (Bpdu), 84, 527

bridges, 7, 7–8, 527

and collisions, 70

design considerations, 74

segmentation with, 70–71, 71

vs. switches, 74

bridging protocols, 382–392, 383

exam essentials, 393–394

integrated routing and bridging, 390

source-route bridging, 390–391

source-route translational bridging, 392

source-route transparent bridging,391–392

transparent bridging, 384, 384–390

filtering packets, 387–388

forwarding packets, 385–386

learning MAC addresses, 384–385

loop avoidance, 388–390

broadband, 527–528

broadband ISDN (BISDN), 527

broadcast addresses, IP v6 and, 296

Broadcast-and-Unknown Server (BUS),48, 528

broadcast domains, 73, 528

broadcast storms, 7–8, 78, 78, 388–389, 528

blocking, 92

Spanning-Tree PortFast and, 386–387

broadcasts, 39–40, 528

control, 90–91

preventing forwarding, 27

buffer, 528

buffering, 24

Building Access-sub-module, 198

Building Distribution sub-module, 198

bulletin boards, Application layer for, 18

BUS (Broadcast-and-Unknown Server),48, 528

bus, 528

bus topology, 528

business constraints, 157

evaluating network needs andexpectations, 167

information gathering about, 164

BVI (bridge-group virtual interface), 390

BX.25, 528

bypass mode, 528

bypass relay, 528

byte-oriented protocol, 529